Bending machine

ABSTRACT

A bending machine having a rotatable bending plate which supports bending tools, setting means for setting various principal bending angles, a drive motor for rotating the bending plate and a starting switch for the drive motor, there being also provided an electric pre-selector switch which controls the starting switch and the setting means comprising an annular disc which is arranged to rotate in the same direction and at the same speed as the bending plate, together with a plurality of setting elements in the form of setting pins which can be inserted in predetermined circumferential positions in the annular disc, there being also provided a single pulse transmitter which is engageable by the setting pins to generate a series of pulses as the annular disc is rotated with the bending plate, pulse counting means being also provided and being connected to the pulse transmitter and being arranged to cut out the starting switch of the drive motor after a pre-selected number of pulses has been counted by said pulse counting means.

United States Patent 1 Peddinghaus 111 3,717,016 1 Feb. 20, 1973 [54] BENDING MACHINE [76] Inventor: Carl Ullrich Peddinghaus, Obere Lichtenplatzer Str. 276, 56 Wuppertal-Barmen, Germany [22] Filed: May 13, 1970 [21] Appl. No.: 36,990

52 U.S. Cl. ....72/21, 72/7, 72/30, 72/DIG. 22

51 lm. Cl. ..B2lb 37/08 [58] Field of Search.72/7, 21, 22, 26, 2s, 30, DIG. 4, 72/DIG. 22

[56] References Cited UNITED STATES PATENTS 3,393,543 7/1968 Van Gelder ..72/26 3,512,383 5/1970 Arnold et al. ..72/22 3,387,473 6/1968 Noordhoek et al ..72/22 3,299,681 I-Iautau ..72/7

7 FOREIGN PATENTS OR APPLICATIONS 889,179 2/1960 Great Britain ..72/DIG. 4

Primary Examiner-Charles W. Lanham Assistant Examiner-Michael J. Keenan Attorney-Holman & Stern [57] ABSTRACT A bending machine having a rotatable bending plate which supports bending tools, setting means for setting ,various principal bending angles, a drive motor for rotating the bending plate and a starting switch for the drive motor, there being also provided an electric preselector switch which controls the starting switch and the setting means comprising an annular disc which is arranged to rotate in the same direction and at the same speed as the bending plate, together with a plurality of setting elements in the form of setting pins which can be inserted in predetermined circumferential positions in the annular disc, there being also I provided a single pulse transmitter which is engageable by the setting pins to generate a series of pulses as the annular disc is rotated with the bending plate, pulse counting means being also provided and being connected to thepulse transmitter and being arranged to cut out the starting switch of the drive motor after a pre-selected number of pulses has been counted by said pulse counting means.

6 Claims, 9 Drawing Figures PATENTEU FEBZO 1973 3, 016

sum 3 or 3 INVENTOR 6m! (MM/1 gal- W SfEmU BENDING MACHINE The invention relates to a bending machine for bars, wires and sections of steel and like materials and having a bending plate which supports the bending tools which can be driven in controlled angular directions at an angle of rotation which can be predetermined, there being further provided setting means connected to the bending plate for setting the various principal bending angles to the elements of the setting means corresponding to the principal bending angles controlling a starting switch of a drive motor when the latter is in its interrupted position.

Known bending machines of this type are equipped with bolt-like switch feelers, whereas the setting means are pins which are to be inserted at various heights in an annular disc surrounding the bending plate. The setting pins are inserted in holes provided in the annular disc corresponding to the main bending angles, thus, for example, there is a setting pin for bending 45, another for bending 90 and a third for bending 180. The switch feeler set to one of the heights of the pin corresponding to the desired bending angle is then only actuated by the latter and switches off the starting switch of the drive motor. In addition, in this case, two further switches, generally operated by a foot pedal to provide clockwise or anti-clockwise operation of the machine are needed. If, in this case the pins are wrongly exchanged in the annular disc with regard to their length or height, this results in incorrect bends, which are often very difficult and frequently impossible to correct. Thus, for each individual bending operation the operator must pay the greatest attention to his work, particularly since with varying dimensions or changing tensile strengths, the pins are inserted in adjacent holes in the annular disc so as to achieve the bending angle provided. It is also important that the switch for clockwise or anti-clockwise motion is correctly set.

The object of the invention is to provide an improved bending machine of the type described to the effect that the operation is simplified and operator errors of the afore-mentioned type are largely eliminated. In addition, the mechanical movable parts, which always show a certain susceptibility to trouble, are considerably reduced, by means of which a decrease in the manufacturing costs is also achieved.

According to the invention, there is provided a bending machine for bars, wires and sections of steel and like materials having a bending plate supporting bending tools, the bending plate being rotatable and drivable in controlled angular directions, a drive motor for rotating the bending plate, 'a starting switch for the drive motor, setting means for setting various principal bending angles and for controlling the starting switch of the drive motor, an electric pre-selector switch controlling the starting switch, and the setting means comprising an annular disc arranged to rotate in the same direction and at the same speed as the bending plate, a plurality of setting elements defined by setting pins which can be inserted in predetermined circumferential positions in the annular-disc, the pins inserted in the annular disc being disposed in a single plane, a single pulse transmitter sequentially engageable by the setting pins to generate a series of pulses as the annular disc is rotated, a single pulse counting means, the pulse transmitter being connected to the single pulse counting means whereby a predetermined number of pulses, corresponding-to a desired principal bending angle can be pre-selected, the arrangement beingsuch that the starting switch of the drive motor cuts out after reaching the pre-selected number of pulses generated by engagement of the pulse transmitter by the setting pins.

According to an advantageous embodiment of the invention, the pre-selector switch can, in addition, be actuated in both directions of rotation in its varying positions, simultaneously controlling the clockwise or anticlockwise motion of the bending plate. Thus, the operator needs to pay attention solely to a single button, by means of which the danger of an incorrect control is considerably reduced. What is more, since this preselector switchneeds to be operated with only one hand, it is also avoided that two switch adjustments can inadvertently be made at the same time or in the wrong sequence. As will be described later, it is possible to construct this switch at the same time as an indirect or direct starting switch of the drive motor and to give it a zero position in which the switching on of the drive motor is locked. In this case the switching on of the drive motor only takes place when a corresponding bending angle is pre-selected.

The standard setting elements for transmitting the individual pulses can be of varying construction. Thus, advantageously they can be in the form of setting pins which can then be inserted in a setting member constructed in known manner as an annular disc so as to actuate a contact pulse transmitter which is firmly secured to the bending machine.

Although different forms are possible for the construction of the pre-selector switch, that of a rotary switch is particularly advantageous, because this means, that with the best possible facility of inspection, the greatest saving of space is achieved.

The pre-selector switch constructed as a rotary switch can, in addition, appropriately be engaged in an axial direction such that due to this, after a completed pre-selection, the starting switch of the drive motor is actuated. As has already been described, it may be arranged to provide in the zero position a locking against unintentional switching on of the drive motor; I On pressing on the central part of the rotary switch either a lasting engagement can be obtained, which automatically disengages again after the switching off of the drive motor, or due to this a switch device can simply be contacted whereupon the central section of the rotary switch returns immediately to its initial position, whereas the switch device actuates or forms the starting switch of the drive motor.

The parts of the pre-selector switch, with which the clockwise or anti-clockwise motion of the bending plate are controlled and which serve for the contactmaking during the pre-selection of the pulse number, can, for example, lie concentric to each other, in which case corresponding contact springs abut against them. A particularly space saving arrangement is achieved if the pre-selector switch has two sections spaced apart in an axial direction so as to extend inan axial direction according to the engagement movement and of which one is associated with the clockwise or anti-clockwise motion of the bending plate and the other of which serves as a contact-maker during the pre-selection of the pulse number.

Finally several pre-selector switches can be arranged one after the other by means of an additional sequential relay or pulse counter circuit, so that in its entirety they form an automatic stepping bending sequence programme. In this case all individual bends to be produced in reinforcing steel can be pre-selected, according to which the switching takes place and the entire bending programme is carried out automatically.

The invention will now be more particularly described with reference to the accompanying drawings in which: 7

FIG. 1 is a plan view of the bending plate with an annular disc,

FIG. 2 is a side view of the bending plate shown in FIG. 1 of the drawings with the contact pulse transmitter,

FIG. 3 shows a stepping relay circuit,

FIG. 4 is an enlarged detail of the relay contact,

FIG. 5 shows a pulse counter,

FIG. 6 shows a pre-selector switch in side view,

FIG. 7 is a plan view of the switch shown in FIG. 6 of the drawings,

FIG. 8 is a sectional view along the line VIII-VIII of FIG. 6, and

FIG. 9 is a sectional view along the line IX-IX of FIG. 6.-

Referring to the drawings FIG. 1 shows a bending plate 1 supporting two bending tools 2 and 3 which may be bending bolts with round or any other cross sections. An annular disc 4 is provided along its annular center line 5 with consecutive setting holes 6, in which setting pins, corresponding to the main bending angles, are in serted. As shown in FIG. 1, three setting pins 7, 8 and 9, corresponding to main bending angles of 45, 90 and 180, are inserted in the holes 6.

In the side view according to FIG. 2, there can be seen the bending plate 1 and the annular disc 4 surrounding it. The bending bolts 2 and 3 project above the surface of the bending plate 1 from the lower surface of which project the setting pins 7, 8 and 9 which are all located at the same setting height 10. A contactmaker is shown at 11' which always closes a contact in pulse circuit 11 when one of the setting pins 7,8 or 9 passes over it.

In the pulse circuit 11 according to FIG. 3 a stepping relay circuit is included. Three relay stations are shown but as indicated more relay stations can be added to the right-hand part of the circuit if it is desired to have more than three principal bending angles. For the sake of simplicity only the left-hand relay station of the circuit according to FIG. 3 is provided with references. In the pulse circuit there is shown a relay coil 12 which, in the excited condition attracts the relay beam 13 which is pivotally mounted at the point 15 and held in a raised position by means of a spring 14. At point 22, as indicated schematically and as will be described in detail,

mounted at point 18 and which is held by spring 22 against a stop 19 can be disengaged, so that it releases the relay beam 13 which then returns to its position shown in the drawing. At point 23 the relay beam 16, as will be described in greater detail, likewise has two front contacts, one of which is connected in the pulse circuit 11 and the other in a control circuit 21. In the.

latter control circuit 21 there is also connected, as can be seen, the pre-selector switch 24.

FIG. 4 shows the relay beams 13 and 16 in the region of their front contacts. These are indicated in one relay beam 13 at 22' and 22" and lie on upper edge 13 of the relay beam 13. Its underside 13" is shown in a broken line. Below the edge 13' there lies the upper edge 16' of the relay beam 16, on whose lower edge 16" contacts 23 and 23" are located.

When the contact maker 11 according to FIG. 2 is closed, the relay beam 13 is attracted and thus as a result of its oblique sliding surface overcomes the resistance of the spring-loaded relay beam 16. The relay beam 13 then comes to rest against the relay coil 12 and, when the contact .maker 11' opens, is released from the relay coil 12. In this case it is pulled by the spring 14, so that its contacts 22' or 22" come to lie against the corresponding contacts 23 or 23".Thus, however, as can be seen from the circuit and from the previous description, the adjacent relay is connected in the pulse circuit. According to which of contacts a, b or c the pre-selector switch 24 was connected, at the first, second, third or if necessary fourth or fifth pulse a circuit is made in the control circuit 21, which can then interrupt the starting switch of the drive motor.

In place of the described relay circuit there can also be used a pulse counter, as is shown in FIG. 5. In this case, in the pulse circuit 11 there is connected the relay coil 25, which attracts a pivotally mounted ratchet lever 26 in the direction of the arrow. The ratchet of the ratchet lever 26 thus engages on a ratchet wheel 27 and turns the latter by a certain amount, which considering that only a few pulses are to be counted, is comparatively large according to the invention. Incorrect engagements of the, ratchet lever are therefore safely excluded. The ratchet wheel 27 and the ratchet lever 26 have retaining springs which are not shown in detail in the drawing and which are not part of the invention, so that a gradual adjustment takes place solely when the relay coil 25 is excited. The ratchet .wheel 27 is also equipped with acontact arm 29, which is connected by means of a slip ring to line 28 which in turn lies in the control circuit 21. According to the position of the ratchet wheel the contact arm 29 can either contact no contacts or lie against one of contacts 30, 31 or 32, as is shown partially with solid lines and partly with broken lines. The contacts 30, 31 and 32 are connected to contacts a, b and c of the pre-selector switch 24, so that in this case too it depends on the position of the pre-selector switch, as to after how many individual pulses the control circuit 21 is closed. For the ratchet lever 26 there can also be provided an auxiliary relay coil, by means of which on switching off the drive motor, it can be released from its locked position whereupon the ratchet wheel 27, by means of a spring which is not shown, returns to its initial position and is held in that position by a stop.

Apart from the embodiments illustrated in FIGS. 3 to 5 there can also be used electronic pulse counting apparatus.

The pre-selector switch according to FIG. 6 consists of a substantially cylindrical switch body 33 which can be rotated and engaged by means of a rotary button 34. Two switch sections 35 and 36 are each provided with a trip cam 37 or 38. In the central position of the button 34 the cams 37 and 38 do not lie against any contacts. Thus, at the same time, the engagement mechanism, which is not shown in detail is locked, so that a switch 39 for a starting circuit 40 cannot be operated. When the button 34 is turned to the right or, as is shown in the drawing, to the left, the trip cam 37 comes into contact with a half ring, indicated at L or R, as can be seen from Figure 8.

In addition, it depends on the size of the angle of rotation as to which of the three contacts a, b or c the trip cam 38 abuts against. As Figure 7 shows, the operation of the rotary button 34 is very obvious, because one can immediately recognize a rotation to the right or left and a set bending angle of 45, 90? or ll80. The three said bending angles thus correspond to the described contacts a, b and c.

For the right or left-hand direction to be controlled selectively, there is connected according to Figure 8 a further control circuit 42. The trip cam 37 is connected to it by means of a slip ring contact. When, as is shown in the drawing, it lies against the left-hand half-ring, a left-hand relay '41 lying in a control circuit 42 is excited, otherwise the right-hand relay 41 also lying in the control circuit 42 is excited. These two relays actuate a pole-reversing switch 43 which in turn is connected in the starting circuit 40 and therefore bring about an appropriate reversal of polarity.

Figure 9 illustrating the switch section 36 of Figure 6 in section, shows that contacts a, b and c lying on both sides of the zero position are connected to each other so that it is immaterial as to on which side of them the trip cam 38 comes to lie. The trip cam 38 is connected to the control circuit 21 by means of a slip ring contact, whereas closed contacts a, b and c are connected to the corresponding contacts a, b and c of the relay circuit, the pulse counter or an electronic counting apparatus.

The setting elements preferably illustrated as setting pins can also be realized in any other form which fulfils the purpose, as for example, magnetic or photoelectric contacts or the like.

Having thus described my invention what I claims as new and desire to secure by Letters Patent is:

1. A bending machine for bars, wires, and sections of steel and like materials provided with a bending plate supporting bending tools, said bending plate being an electric pre-selector switch, said starting switch' being controlled by said electric pre-selector switch, and said setting means comprising an annular disc arranged to rotate in the same direction and at the same speed as said bending plate, a plurality of setting elements defined by setting pins which can be inserted in redeterminedcircumferential positions in said annuar disc, the pins inserted in said annular disc being disposed in a single plane, a single pulse transmitter sequentially engageable by said setting pins to generate a series of pulses as said annular disc is rotated, a single pulse counting means, said pulse transmitter being connected to said single pulse counting means whereby a predetermined number of pulses, corresponding to a desired principal bending angle can be pre-selected, the arrangement being such that the starting switch of said guide motor cuts out after reaching the preselected number of pulses generated by engagement of said single pulse transmitter by said setting pins.

2. The bending machine according to claim 1 characterized in that the pre-selector switch can be operated in either direction of rotation so as to control the clockwise and anti-clockwise motion of the bending plate.

3. The bending machine according to claim 1 characterized in that the pre-selector switch is constructed as a rotary switch.

4. The bending machine according to claim 3 characterized in that the pre-selector switch which is constructed as a rotary switch can in addition he engaged in an axial direction so that, after a completed preselection by rotary movement, axial engagement of said pre-selector switch will actuate said starting switch of the drive motor.

5. The bending machine according to claim 4 characterized in that the pre-selector switch has two sections which are spaced apart in an axial direction and which extend in an axial direction, one of said sections being associated with the rotary movement of the bending plate and the other section serving as a contact-maker during the pre-selection of the number of pulses.

6. The bending machine according to claim 1 characterized in that several pre-selector switches can be arranged one after the other by means of an additional sequential relay or pulse counter circuit which in its entirety forms an automatic stepping bending sequence programme. 

1. A bending machine for bars, wires, and sections of steel and like materials provided with a bending plate supporting bending tools, said bending plate being rotatable and driveable in controlled angular directions, a drive motor for rotating said bending plate, a starting switch for said drive motor, setting means for setting various principal bending angles and for controlling said starting switch of said drive motor, an electric pre-selector switch, said starting switch being controlled by said electric pre-selector switch, and said setting means comprising an annular disc arranged to rotate in the same direction and at the same speed as said bending plate, a plurality of setting elements defined by setting pins which can be inserted in predetermined circumferential positions in said annular disc, the pins inserted in said annular disc being disposed in a single plane, a single pulse transmitter sequentially engageable by said setting pins to generate a series of pulses as said annular disc is rotated, a single pulse counting means, said pulse transmitter being connected to said single pulse counting means whereby a predetermined number of pulses, corresponding to a desired principal bending angle can be pre-selected, the arrangement being such that the starting switch of said guide motor cuts out after reaching the pre-selected number of pulses generated by engagement of said single pulse transmitter by said setting pins.
 1. A bending machine for bars, wires, and sections of steel and like materials provided with a bending plate supporting bending tools, said bending plate being rotatable and driveable in controlled angular directions, a drive motor for rotating said bending plate, a starting switch for said drive motor, setting means for setting various principal bending angles and for controlling said starting switch of said drive motor, an electric pre-selector switch, said starting switch being controlled by said electric pre-selector switch, and said setting means comprising an annular disc arranged to rotate in the same direction and at the same speed as said bending plate, a plurality of setting elements defined by setting pins which can be inserted in predetermined circumferential positions in said annular disc, the pins inserted in said annular disc being disposed in a single plane, a single pulse transmitter sequentially engageable by said setting pins to generate a series of pulses as said annular disc is rotated, a single pulse counting means, said pulse transmitter being connected to said single pulse counting means whereby a predetermined number of pulses, corresponding to a desired principal bending angle can be pre-selected, the arrangement being such that the starting switch of said guide motor cuts out after reaching the pre-selected number of pulses generated by engagement of said single pulse transmitter by said setting pins.
 2. The bending machine according to claim 1 characterized in that the pre-selector switch can be operated in either direction of rotation so as to control the clockwise and anti-clockwise motion of the bending plate.
 3. The bending machine according to claim 1 characterized in that the pre-selector switch is constructed as a rotary switch.
 4. The bending machine according to claim 3 characterized in that the pre-selector switch which is constructed as a rotary switch can in addition be engaged in an axial direction so that, after a completed pre-selection by rotary movement, axial engagement of said pre-selector switch will actuate said starting switch of the drive motor.
 5. The bending machine according to claim 4 characterized in that the pre-selector switch has two sections which are spaced apart in an axial direction and which extend in an axial direction, one of said sections being associated with the rotary movement of the bending plate and the other section serving as a contact-maker during the pre-selection of the number of pulses. 